1. Field of the Invention
The present invention relates to a mobile communication apparatus, a method, and a computer readable medium thereof; more specifically, it relates to a mobile communication apparatus, a method, and a computer readable medium thereof for early measuring a signal of a base station to determine whether to change connections.
2. Descriptions of the Related Art
With the universality of mobile communications, there have been increasingly more types of and more numbers of mobile communication apparatuses that have been developed. Currently, most mobile communication apparatuses on the market, such as mobile communication apparatuses adopting globe system for mobile communications (GSMs), wideband code division multiple accesses (WCDMAs), general packet radio services (GPRSs), personal handy-phone systems (PHSs), or worldwide interoperability for microwave accesses (WiMAXs), provide services, such as wireless voice, wireless video, and data communication, through base stations. Any of these mobile communication apparatuses can access various related services via the mobile communication network system once a connection with a base station has been established.
However, the mobile communication apparatus must handoff from one base station to another base station to ensure that communication services will not disconnect while the mobile communication apparatus moves among the base stations. FIG. 1 depicts a common connection between a mobile communication apparatus and a base station. FIG. 1 includes a first base station 101, a second base station 103, a mobile communication apparatus 105, and a base station controller 107. The first base station 101 has an effective communication coverage 100. The second base station 103 has an effective communication coverage 102. The base station controller 107 commands the mobile communication apparatus 105 to measure signals of neighboring base stations and to report measured results. After that, the base station controller 107 commands the mobile communication apparatus 105 to switch the connection according to the measured results of the base stations. For example, the mobile communication apparatus 105 can be originally within the effective communication coverage 100 of the first base station 101, and be able to establish a connection with the first base station 101 to access communication services. If the mobile communication apparatus 105 starts moving closer to the second base station 103 and moving into an overlap area 104 of the effective communication coverage 100 of the first base station 101 and the effective communication coverage 102 of the second base station 103, the base station controller 107 will command the mobile communication apparatus 105 to measure the signals of neighboring base stations and to report the measured results, which comprise signals of the first base station 101 and the second base station 103. The mobile communication apparatus 105 measures that both the signals from the first base station 101 and the signal from the second base station 103 can be available in the overlap area 104. When the signal from the second base station 103 has priority over the signal from the first base station 101, the mobile communication apparatus 105 will switch the connection. That is, the base station controller 107 commands the mobile communication apparatus 105 to switch the connection from connecting with the first base station 101 to connecting with the second base station 103 so that the communication between the mobile communication apparatus 105 and the preferred base station can be maintained.
The aforementioned procedure of switching connections is a common technique for mobile communication systems. If the fast moving mobile communication apparatus 105 moves through the overlap area 104 too quickly, the base station controller 107 is too late to command the mobile communication apparatus 105 to measure and report the signals of neighboring base stations. As a result, the mobile communication apparatus 105 will leave the effective communication coverage 100 of the first base station 101. Therefore, there will be a failure in switching connections and results in the discontinuity of the communication service taken by the mobile communication apparatus 105.
Therefore, a method for creating a mobile communication apparatus that can not only measure signals of neighboring base stations in time during high speed movement, but also smoothly switch connections among the base stations is still needed.